Cuaderno de viaje

De interés geológico

Geological interest

Somontano provides a perfect opportunity to learn how the landscape around us was formed. A visit through the region reveals signs of geological processes that explain the existence of mountains and valleys, canyons and stone pillars, rocky outcrops and cliffs.

Start your journey here to see the main points of geological interest in Somontano.

La Fondota, Paleontological Site. Abiego

At the entrance to Abiego on the road from Bierge there is an interesting collection of over 1000 ichnites preserved in a layer of limestone. They are the fossilized footprints of herds of herbivores, now extinct, that lived on what were meadows dotted with small lakes. They are thought to correspond to the artiodactyla group of mammals, possibly the Anoplotherium or Entelodon.

Between 35 and 40 million years old, they date back to between the Eocene and Oligocene periods. Originally left in mud, the footprints filled with leaf and plant residue, which protected them from erosion.

Muelas of El Tormillo and Terreu, tabular relief. El Tormillo

These table-top hills are located to the south of Somontano. Before the Alpine orogeny occurred, sediments of different matter settled horizontally and, layer by layer, built up a stratum of diverse compositions. (limestone, clay, loam etc.) Later, the erosive effects of a network of rivers gave rise to these distinctive hillocks. They are all that remains of a large surface area and now sit isolated between wide valleys that were patiently carved by the erosive force of the rivers.